I could not find "Calculated Number Field" when I clicked on "Add custom field" in JIRA. Is this no longer existing any more?
Calculated Number Field is not a standard custom field, so I suspect that you previously used a JIRA instance that had https://innovalog.atlassian.net/wiki/display/JMCF/JIRA+Misc+Custom+Fields installed on it. Although there are other alternative plugins that provide comparable functionality.
It is worth checking your add-ons to see if the add-on is installed but not enabled as well.
It looks like you're new here. Sign in or register to get started.